According to the design of an electrically connecting structure of piezo-electric plates, the prevent inventor has disclosed in R.O.C. (Taiwan) Patent Publication No. 527067, R.O.C. (Taiwan) Patent Publication No. 527063, R.O.C. (Taiwan) Patent No. M252149 and R.O.C. (Taiwan) Patent Publication No. 535999. In conventional technology, an anode and a cathode of the input end of the piezo-electric plate are individually electrically connected to electrodes of power supply of a circuit board by a welding manner of electrically connecting line material or a pressing and connecting manner of electrically conductive and elastic sheet so as to form a circuit. According to the trace layout of the circuit board, all positions of electrodes of power supply of each piezo-electric plate are divided and separated from one another. The dimension of an electronic device (such as a liquid crystal display television) is gradually increased, and thus the number of the piezo-electric plates is much gradually increased. For above reason, not only the size of the trace layout of the circuit board is much gradually increased, but also the manufacture of the trace layout of the circuit board is difficult because of complexity.